Evaluating the optimum operating parameters on transesterification reaction for biodiesel production over a LiAlO2 catalyst

The LiAlO2 catalyst was prepared by solid-state reaction and then applied to the biodiesel production by transesterification reaction between methanol and soybean oil. This was the first attempt to use LiAlO2 as a catalyst for biodiesel production. It was found that the catalyst of 4 (mol(Li2CO3)/mol(Al2O3)) being calcined at 900 °C showed the optimum activity. XRD, BET and FE-SEM demonstrated that the Li compound was incorporated into Al2O3 to form LiAlO2 with an enhanced basicity. The maximum conversion achieved 97.5% with 2 h reaction time at 65 °C, 24:1 M ratio of methanol to oil and 8 wt.% of catalyst. LiAlO2 could be easily recovered and reused for six cycles without significant deactivation.